PausedComposition

fun apply(): Unit

Apply the composition. This is the last step of a paused composition and is required to be called prior to the composition is usable.

Calling apply should always be proceeded with a check of isComplete before it is called and potentially calling resume in a loop until isComplete returns true. This can happen if resume returned true but apply was not synchronously called immediately afterwords. Any state that was read that changed between when resume being called and apply being called may require the paused composition to be resumed before applied.

fun cancel(): Unit

Cancels the paused composition. This should only be used if the composition is going to be disposed and the entire composition is not going to be used.

fun resume(shouldPause: ShouldPauseCallback): Boolean

Resume the composition that has been paused. This method should be called until resume returns true or isComplete is true which has the same result as the last result of calling resume. The shouldPause parameter is a lambda that returns whether the composition should be paused. For example, in lazy lists this returns false until just prior to the next frame starting in which it returns true

Calling resume after it returns true or when isComplete is true will throw an exception.

val isApplied: Boolean

Returns true when the PausedComposition is applied. isApplied becomes true after calling apply. Calling any method on the PausedComposition when isApplied is true will throw an exception.

val isCancelled: Boolean

Returns true when the PausedComposition is cancelled. isCancelled becomes true after calling cancel. Calling any method on the PausedComposition when isCancelled is true will throw an exception. If isCancelled is true then the Composition that was used to create PausedComposition is in an uncertain state and must be discarded.

val isComplete: Boolean

Returns true when the PausedComposition is complete. isComplete matches the last value returned from resume. Once a PausedComposition is isComplete the apply method should be called. If the apply method is not called synchronously and immediately after resume returns true then this isComplete can return false as any state changes read by the paused composition while it is paused will cause the composition to require the paused composition to need to be resumed before it is used.